Today we look at the results of yesterday’s tune on Geo791’s .22 caliber Diana RWS 34P. I talked to Tom Gore, the owner of Vortek, and asked what kind of results I could expect from this kit. He said this one was designed to make the rifle perform at the factory spec, but with much longer spring life. When I told him how the rifle had tested before he said he felt it was right on spec already. I felt so, as well. And of course that was with a broken mainspring.

How to tell if the mainspring is broken

Several of you have asked me whether it’s possible to know when a Diana mainspring has broken and I said no. If just one end of the spring is broken the gun will shoot smoother than before and will have the same velocity. I think the broken piece winds itself into the new end of the mainspring (it always does) and helps dampen vibration. Unless you are observing the performance of your rifle very carefully and watching for this you’ll never see it.

Of course when the other end breaks, as it often does, the rifle gets even smoother and easier to cock. But at that point a .22 will lose about 150 f.p.s.

So, Georges’ rifle was both smooth and powerful when I initially tested it. I said that in Part 2. Let’s see what the Vortek tune did. I will test it with the same pellets I used in Part 2, so everything is the same except the tune.

Tight piston seal

Several readers asked about the possibility of putting an o-ring in the groove that runs around the circumference of the piston seal. That is impossible. This new seal fits the compression chamber extremely tight. I had to use a screwdriver to ease it past all the cutouts in the spring tube, so the seal did not get cut.

That groove sqwishes down much smaller when the seal goes into the spring tube. It’s there to prevent excess lube from migration forward. George won’t have to worry about that because I applied the special grease very sparingly.

JSB Exact RS domes

The first pellets I tested were JSB Exact RS domes. They averaged 639 f.p.s. in the before test, with a 25 f.p.s. spread. This time they averaged 627 f.p.s. and the spread was 28 f.p.s. — from 613 to 641 f.p.s. That’s a bit of a drop. Before it produced 12.07 foot-pounds and this time it produced 11.73 foot pounds

RWS Superdomes

RWS Superdomes were next. These 14.5-grain pellets averaged 701 f.p.s. in the first test and 689 f.p.s. with the Vortek tune. The spread was initially 16 f.p.s. and this time it was 62 f.p.s. because of one slow shot. That one went 641 f.p.s., but it was an anomaly because the next slowest shot was 689 f.p.s. The high was 703 f.p.s. In the first test this pellet developed 15.83 foot pounds. After installation it develops 15.29 foot pounds.

RWS Hobbys

Next up were some 11.9-grain RWS Hobbys. In the before test they averaged 736 f.p.s. with a 39 f.p.s. spread. This time Hobbys averaged 727 f.p.s. and the spread was 37 f.p.s. That’s pretty close to last time. The muzzle energy was 14.32 foot-pounds in the first test and 13.97 foot-pounds this time.

Where are we?

I bet you didn’t expect those numbers — did you? I didn’t either. I do know that as this tune breaks in after several hundred shots the average velocities will rise just a bit, perhaps to where they were with the factory mainspring.

Why isn’t it any faster? Well, in my experience this Diana 34 was right where I expect all the good ones to be. Making it go faster serves no purpose unless it comes with some kind of benefit, like improved accuracy or smoother operation. Since tunes seldom affect accuracy I doubt a faster gun would offer us anything, and it is already shooting very smooth.

Did the rifle smooth out?

It’s difficult to say whether the rifle smoothed out because it was smooth before. I told you that when I tested it. Smooth shooting is one characteristic of Diana rifles that have broken mainsprings. They are already very smooth from the factory and when the spring breaks they get very calm.

So — is this rifle any smoother? I’m going to stick my neck out and say yes. I believe it is. The difference is very small because the rifle didn’t have very far to go, but I do believe I can feel a small improvement.

Cocking effort

Here the Vortek kit will suffer, because the rifle with the broken mainspring was already cocking very easy. Diana’s always get easier to cock when the spring breaks. I measured the force needed to cock the rifle now and it comes to 35 pounds on my bathroom scale. Before it was 28 pounds. So the effort has increased. Diana rates the cocking effort of a model 34 at 33 pounds, so one might say the rifle is back to factory specs.

What are the advantages?

This test has produced some surprising results, hasn’t it? We all want the ending to be like when Bob Beamon broke the world long jump record at the 1968 Olympics by almost 2 feet, but life isn’t always like that. Often the victory is measured in inches and sometimes, like today, it stays the same or even goes backwards. So, has anything been gained?

Absolutely! First, take another look at Geroge’s broken mainspring. Not only was one end snapped off, the other end is canted and will probably break as well. The Vortek kit has put an end to that fear. George’s 34P will still be shooting this fast or faster 10,000 shots from now.

Next, the powerplant has been lubricated for an indefinite period. George never has to worry about oiling the piston or greasing the mainspring because the materials I’ve installed probably have a good 10 years of life in them — maybe more.

And finally, the rifle does shoot very smooth. This time it’s not because of a broken part but because all the tolerances have been reduced to a minimum and then lubricated with just enough of the right grease.

The rest of the story

I said in an earlier installment that I have a plan to fix George’s drooping problem for him. I’m not going to tell you what it is today, but next time I will mount a scope that’s similar to the 4-12 George owns, and shoot for accuracy at 25 yards again. We now know which pellets it likes.

If everything works as planned, the mount I will use will allow the scope to be adjusted in the center of its elevation range, which may help George with his fliers. The mount maker has agreed to donate this mount to George, so when he gets his rifle back all he has to do is remount his own scope.

If the guns cock easier and don’t lose velocity they may not be getting enough customer complaints to be aware of the problem. The better question might be ” Why do you make your springs so long when shorter works better, Diana?”

It seems the springs are vulnerable on both ends, and when both ends break there is a dramatic change. I think Diana just don’t give a s*** about droop or broken springs. They believe their rifles are “good enough” and they are probably right.

Just goes to show that the subculture of a company can overwhelm Germanic propensity for precision.

I wonder if they smooth out with one break due to a shorter spring or a “floating head” effect which works really well for savage rifles at centering things.

On the whole “Barrel Droop” issue, why is it always droop? If it’s not deliberate, why don’t we read about Left Cocked or Right Biased or Sky Pointed barrels. If it were the inability to bore a straight hole in round bar or to press a perfectly drilled barrel 2″ into a steel block, it seems you’d have complaints even when using iron sights. They run out of adjustment too. It must be on purpose but I sure as sugar can’t figure out why, can you?

I worked from 10:00 PM to 6:00 AM for over 40 years and I’ve been retired for a little over a year and a half and still haven’t quite adjusted to an “up in the daylight, down at night ” life style. What’s your excuse for being up at this hour.

Duh, I feel kinda dumb right now. I assumed Theaussie was a last name or a town somewhere. Didn’t separate the “the” out of it. Most Yanks are smarter than me so don’t judge the rest of them. 🙂 Would love to visit your country. Really high on my bucket list but time is running out. You guys gotta get those gun laws changed, though. What IS the time there?

Bent barrels don’t matter. Well, maybe they matter. I don’t know, but I have my doubts that they matter regarding accuracy. They complicate scoping and sights, but the below is an exceptionally accurate 10 meter pistol.

Halfstep
Many years back (late ’70s) I bought my first air rifle (FWB 124) from Air Rifle Headquarters (ARH – the original). I was a big fan of Robert Law and read as much of his writings as I could and even corresponded with him. His position was that German air rifles were made for the German style of shooting which was mostly off hand and with open sights. Americans wanted to “scrunch” down with their aiming eye as close to the receiver as possible and utilize a rear placed peep site in the military style. If you take a Diana with open sights your aiming eye just naturally aligns with the front and rear sights in the off hand position, as long as you have that droop.
When he sold his rifles, barrel straightening was an option for anyone wishing to mount a scope.

Thanks for that bit of history and insight into the “droop” issue. I have two RWS rifles and I have their open sights stored and I even know where they are. I can remount them and experience that alignment first hand. My first gun was a FWB 124 also. I still have it but, alas, I mounted the rear sight on one of those cheap Chinese under levers a long time ago. I think I had to modify it in such a way that it can’t go back on the 124. I remember Robert Law from back in the day but you’ll have to remind me of his role in airgun lore.

On the droop and spring topic,.. that is what has steered me away from them. Sure, they build a fine gun and they have many hard core followers. No one can argue with that. For me,.. it just comes down to principal. To have an issue(s) and not fix it (them),… just does not sit well with me. But hey, that is just my 2 cents.

Not sure what you call “my 2 cents” over your way, but here it does not mean much and sure will not buy anything. And a bit of an interesting side note,.. it cost more to make a penny (cent) than the penny is worth.

Australia copied dollars and cents from you lot. Ours is worth about 76 of your cents. We aren’t however, silly enough to spend more on making money than it is worth. 1 and 2 cent pieces went out of circulation a decade ago.

I certainly understand refusing to buy a flawed product on principle. I am currently looking for a denim jacket, my first stop was the legendary Levi’s Trucker. When I saw, and tried to fit my wallet in the pathetic little chest pockets I almost had a fit. Will certainly never buy one out of principle. I am currently wearing a cheap jacket that fits me like a tent and still looking for a good one.

Diana don’t care about scoped shooters so scoped shooters shouldn’t consider Diana (unless they want a pretty bloody good rifle for the price)

Diana also offends me for taking a goddess’ name in vain. (I am a big fan of ancient Greece and Rome) Just seems unwise to me.

As a lifelong resident of (sad) State of Illinois, I have insight as to why the U.S. clings to its one cent piece. (Penny is just our nickname for it.) First is that Illinois is “The Land of (Abraham) Lincoln.” Lincoln is on the penny (incidentally the five dollar note as well). Lincoln was also the first President from one of the two ruling political parties that survive to this day, the Republicans, He also is one of only three Republican Presidents all progressive Democrats love very much. Plus Lincoln was assassinated, so he is a sympathetic figure here. Also, Illinois is the fifth largest state, so we have enough Electoral College votes that presidential hopefuls curry our favor.

There was a long discussion on the blog about droop in Diana products some years ago. I think the drift of it was that droop was originally created as a modification to firearms manufacturing methods to compensate for the different trajectory of airguns. Once this became institutionalized with Diana’s success, there was never a reason to change it.

As for the 1 cent piece, that seems trivial, but it also allows everyday transactions to be precise. With the volume of transactions in an economy, these discrepancies could increase to something huge. If one wanted to do away with the penny, you would have to figure all costs in terms of the lowest denomination, like a five cent piece. But then retailers would not be able to charge prices like $59.99. 🙂 But I’ve got no explanation for a 2 cent piece.

I’m with you – I have been debating getting a springer for a while now and Wiehrauch and Diana were on the short list. Far as I am concerned, any vendor that doesn’t take steps to correct known faults in their product won’t get my sale. I don’t need to be spending extra money on special scope mounts and repairs to fix design and manufacturing issues.

Diana’s are nice, the 34 series and 54 perhaps being the nicest. And George’s 34P is now pretty special for the longevity B.B.’s tune has added to it. Diana has in envious pedigree with classics such as certain versions of the Model 25, 27 and 50, and as B.B. has mentioned, the 34 has improved a lot over the years.

Still, they are only slightly less pricey than HWs. Just my opinion, but the Rekord trigger alone makes a Weihrauch worth the extra money at each power level of springer. They are not without faults, but anything imperfect with an HW isn’t better with a Diana.

Springers are so advanced now that the competition for market share must be vicious.

Since you’ve owned both calibers, which has the smoothest shot cycle, or are they the same? Also did you tune yours in any way. And do you have any thoughts on the Vortek kits for these guns.( I think I just saw two kits offered on their website,a full power and a target kit)

The 54 Air King shoots as smooth as a FWB 300. And is probably just as accurate.

But the 300’s trigger is way better. You know how good they are from having yours. But not to say the 54’s trigger is bad. I like the 54’s trigger too. Just can’t be adjusted like the 300’s.

Matter of fact one of shooters from the USA feild target team uses a modified 54 Air King made into bullpup if I remember right. Can’t remember which one of the shooters off the top of my head right now.

Vana2: You won’t regret going with the HW-30S. I bought one and it was my first high quality airgun purchase. If I’m being honest with myself I would have been had all the rifle I needed one I bought it and it’s only acquisitiveness that kept the collection expanding in the years since.

The HW30S is a great little gun but don’t assume new Weihrauch’s are immune from faults. Search HW30 galling issues. You will find a lot on British forums regarding this.
On the other hand you might be lucky with yours. Some are fine.

I think BB may have said they smooth out because the broken piece winds itself into the larger piece and dampens some of the vibration. I assumed that the spring was bending at both ends at the same time and one end would break first then the other would break later mainly because it was strained and bent earlier. If it was just shorter to begin with maybe neither end would bend, strain or break and you get easy cocking in the bargain.

B.B. has often asserted that having a much longer spring installed in a rifle will not increase power “by its lonesome.” Power is increased by a greater volume of compressed air. So, increase the overall powerplant size for more power. Have a larger diameter everything and a longer everything, spring, piston, and chamber, and increase the cocking stroke (and effort) to squeeze it all together. Yes? That is probably how it is done in Turkey.

Read B.B.’s report entitled “Steel Dreams.” That reminds me, the official specs don’t say so, but I’ll bet Diana 34P Pro Compacts average an extra pound or so of energy than the standard models.

I understood that, re: “by its lonesome” (Sorry. I started typin’ that and about half way into it I realized I didn’t have a clue how to punctuate it, but I couldn’t stop) 😉 My point was, since the long spring does not give more power, why not use a shorter one that may not break as easily and will yield an easier cocking stroke? Why aren’t you in bed? I bet BB uses that expression, he lives in Texas ,after all!

I’m a human who was only joking about “visitor to your world.” My wife and I watched a classic (well, sort of classic) sci-fi movie after dinner and I was feeling goofy. I am up only because I am a lifelong insomniac and this is one of those nights,

I have a vintage Weihrauch HW77 with a slightly shorter spring in it, “to detune it” just a little. It cocks maybe four or five pounds easier and is a very smooth shooter. I got it in trade from the fellow who put the new, slightly shorter spring in it. I got extra trade value for that modification, but the truth is that his mod was why I wanted it, just to plink from my patio table. It ended up being a bit heavy for that, but man is it smooth and accurate.

I didn’t know it was broadly true, but in this gun, it just seems a shorter one is in order. Next time some corporate type at Diana wants to shave a few pennies off production costs they will take it out on the end of their mainsprings! 😉

Very nice. A new mount too huh? That is a real tease. Looking forward to see it in action. Very anxiously awaiting the accuracy phase.

The drop in fps does not seem out of the norm. It is a different spring after all. From the TX spring stats that I posted yesterday, they are quite different in length and wire diameter. Most likely the same here. Plus, GF1 did test with the factory seal and the Vortek seal in a TX200 and found the Vortek seal to be a bit slower. Knowing that at the time and having the same gun, I just left the factory seal in. I think this one will break in just fine.

My take on it is that the spring most likely is of different wire diameter, based on my TX kit, and it is longer. That alone would dictate that the FPS will change. I think Vortek did a good job of a match up and still doing their kit. I think we can all agree that the “too much spring” thing is epidemic.

I ask that care be given toward your usage of words on this blog. We have been blessed with this way to express ideas and communicate with others on these topics. There are those who would be offended should we become a bit rough in our language and it serves no real purpose.

It’s odd that the internet is full of reviews and articles on the Sheridan rifles, but very little is available for the Sheridan pistols. The pumpers and the CO2 model pistols have very little information on the internet about the two guns. That also applies to the Benjamin E Series CO2 pistols. YouTube has a few videos on the E Series Sheridan and Benjamin CO2 gun.

The history of the rifles is well documented on the net, but not so the pistols. If someone has any good internet sites that covers these guns, please share the information.

Yes I agree I also have an e series Benjamin co2 pistol in .22 that needs repair, I’ve not been able to find anyone to look at it. It’s a great gun all steel, brass, and wood, it wasn’t expensive but felt like it should have been. I would love to get it up and running again.

B.B.
Yes, I was expecting something a little different. I thought that fps would have increased, not decreased. Though they are close to the same. Thankful that you installed the Vortek kit and now I won’t have to worry about a broken mainspring any longer. Maybe the slower fps is due to the tight fitting seal and once broken it will be better.

Wow! Another donated part…that’s wonderful. BTW, my scope is a Hawke HD 3-9x50AO in case you forgot. Another thing too, when you were shooting with the open sights for the best group, you only achieved less than 1″ with the one JSB 18.1gr pellet. The others you tried gave some similar results as I have had, though a tad better without any flyers. I have had at least one or two flyers in most of my 10 shot groups. I am having the same issue with my Crosman Nitro Venom .22 also. I’ve been shooting that while you have my RWS 34. No matter what I do, or how I hold, I can not for the life of me get those groups that I desire. It has to be me and something that I’m doing wrong.

Guess I may as well shoot the Superdomes up in my Crosman because they sure were not shooting good for you in the RWS 34. I am going to wait until I see the results of your next shooting session before ordering any more pellets. If they are not accurate for you, they definitely won’t be for me either. Good luck and keep up the great work.
Geo

No surprises there, I like Vorteks piston seal but the rest of the “tune” is just binding it all up tighter than a ducks bottom, no thought to taking vibration out and increasing efficiency by encouraging (controlled) natural spring rotation just bind it on up good and tight and let the lack of tolerance damp out the inevitable buzz, still, makes a change from the various levels of filling it up with gloop of elaborate consistencies I suppose.
I wish someone in the US would scratch their heads looking in a TX200 or Walther LGV and ask themselves why they shoot so smoothly even when all but dry yet not need a mallet to get the spring guide in. A real tune lies in the answer to that question.

I agree, but it is a quick, drop in fix for a lot of airguns. And in light of Diana spring issues,.. you are getting a new spring. With the TX200, there was at least 2 kits to choose from, if not 3. That is a plus for someone wanting to de-tune/lower power.

I like the assertion that the broken spring piece provided some dampening. My thoughts have been along the lines of a teflon helix threaded in alongside the spring to provide dampening with out slowing down the spring action.

Perhaps. I think that some semblance of maintaining tolerances would be desired though. That would be tough with a spray on, hard/semi-hard cured coating. It might be something to try on a cheap springer and then tear it back down after 200 shots. If it were to fail, I think that it would do it by 200 shots.

Yes, that would be a good idea, but again it would be difficult to maintain any kind of tolerances to ID and OD. A “watered down” version might be good with multiple dips so that the thickness could be built up (very) gradually. ? Who knows? What I do know is that,… I am out’a here.

Just so that we are clear,.. powder coat is a paint, in powder form, sprayed on with electrostatic help, fired in an oven to around 400 degrees, melted, allowed to cool,… process done. I am not sure that there is anything “lubricious” about it.